Question

2 cubes each of volume 64 cm^3 are joined end to end. Find the surface area of the resulting cuboid.

Answer 1

Find the length of the cube:

Cube = Length x Length x Length

Length³ = 64 cm³
Length = ∛64
Length - 4 cm

When two cubes are placed end to end:

Find Dimenision:

Length = 4 + 4 = 8 cm
Width = 4cm
Height = 4cm

Find Surface Area:

Area of the top and bottom faces = 2 (8 x 4) = 64 cm²

Area of the 4 lateral faces = ( 8 + 8 + 4 + 4) x 4 = 96 cm²

Total Surface area = 64 + 96 = 160 cm²

Answer: Surface Area = 160 cm²

Answer 2

Volume of each cube=
`64 \: cm {}^(3)`
So,edge of each cube =
`\sqrt[3]{64} = 4`
If we join two cubes, then length of cuboid so formed = (4 + 4) = 8.0 cm
Breadth of cube = 4.0 cm
and Height of cube = 4.0 cm

Therefore, surface area of resulting cuboid
= 2 × [lb + bh + hl]
= 2 × [8 × 4 + 4 × 4 + 4 × 8]
= 160 cm²